A challenge for the minimally invasive exploration and treatment of internal areas of the human anatomy continues to be adequately visualizing the area of concern. Visualization can be especially troublesome in minimally invasive procedures in which small diameter, flexible and elongate instruments, such as catheters, endoscopes, or more specifically, ureteroscopes and duodenoscopes, are navigated through natural passageways of a patient to an area of concern, either in the passageway or in an organ accessible through the passageway.
Ureteroscopy is a procedure that is used to diagnosis and/or treat urinary tract diseases such as urinary calculi and ureteral strictures. An ureteroscope is inserted through the urinary tract and diagnosis and/or treatment occurs under direct visualization. Ureteroscopes are typically 2 mm to 3 mm (7 Fr. to 10 Fr.) diameter and include a sheath that encapsulates a fiber optic element, an illumination element and a working channel. Ureteroscopes provide a lumen for instrument access to tissue through the distal tip of the scope: a “working channel” or “forceps channel”, permitting passage of devices, such as guidewires, optical fibers for delivery of laser energy and stone retrieval baskets. The working channel is also used for introducing sterile irrigant. Illumination is typically provided via an optical fiber bundle, terminated within the distal tip of the scope, transmitting light from a source outside of the body. Visualization is afforded via an imaging optical fiber bundle or, more recently, via a CMOS camera chip at the distal tip. Most ureteroscopes also incorporate a steering mechanism, which allows the distal tip of the scope to be deflected in one or more planes to follow the lumen with minimal trauma.
Prior art ureteroscopes/duodenoscopes are not disposable and require extensive, expensive maintenance and are costly to use and maintain for a variety of reasons. A scope must be cleaned and decontaminated/sterilized following each urological procedure (before reuse), potentially delaying successive procedures unless multiple scopes are available. Scopes suffer damage in use that ranges from scratches to working channel liners in passing instruments to a laser fiber burning through the side of the device, to broken steering mechanisms and require regular repair. Many ureteroscopes and duodenoscopes are incompatible with sterilization methods readily available in surgical centers. Decontamination or sterilization delays and costs associated with purchasing and/or repairing scopes have escalated the costs for ureteroscopic and other medical procedures that utilize similarly configured devices.
Illumination and imaging fiber optic bundles are frequently damaged prior to a scope being taken out of service, reducing the quality of direct visualization available between repairs, prolonging surgery and risks to the patient. Direct visualization may also be compromised with a fully operational scope, where irrigation flow is inadequate for removal of surgical detritus, as is the case when inserted instruments block a considerable portion of the working channel lumen. Scopes that cannot be sterilized between uses (and even those that can be and are sterilized) add a risk of infection, such as the famous Olympus TJF-Q180V duodenoscope cross-contamination cases (circa ˜2008 to 2016).
A high degree of flexibility (or “deflectibility”) and minimal diameter at and near the scope tip are prized characteristics for many surgical procedures. Fiber optic bundles occupy considerable space within the scope diameter and are expensive to maintain. Alternatives that eliminate the illumination and imagining fibers permit reduction of scope diameter, reduced resistance to deflection (and therefore smaller deflection wires), and thus offer a potential for provision of separate irrigation and working channels for reproducible surgical filed clearance.
Prior art devices use fiber optics for either illumination or visualization or both. The complexity and cost of devices using fiber optics for at least visualization has been precluded single use in flexible endoscopy. Early solutions for single use sought to minimize the cost by making the patient contacting portion of the scope disposable while reusing the scope handle/control section. The first flexible endoscope to be marketed as single use, Boston Scientific's LithoVue™, utilizes a CMOS camera chip and Light Emitting Diode (LED) to reduce costs, but the overall diameter of the tip remains relatively large at 3.2 mm (10.8 French) and the 3.6 Fr (1.08 mm bore) working channel must also deliver sterile irrigant and drain surgical detritus. The single illumination LED is adequate for most surgical applications, but its position adjacent the camera chip produces non-uniform lighting that lacks flexibility in illumination conditions useful in some surgeries.
It would be useful to provide a small diameter, flexible ureteroscope or duodenoscope or similar device that provides superior illumination and visualization with adequate irrigation and instrument access, within a single use package. Devices would be provided as sterile, reducing infection risks, for safe disposal following the procedure.